Separate the create and start phases in TaskSchedulerImpl.

base/test/scoped_task_scheduler.cc

Index: base/test/scoped_task_scheduler.cc
diff --git a/base/test/scoped_task_scheduler.cc b/base/test/scoped_task_scheduler.cc
index 3c5b0e2fc7807a6b14ecddd640109a46c26aa417..5a01f57e8a37d427b4d458c9700684ed12d1f3e2 100644
--- a/base/test/scoped_task_scheduler.cc
+++ b/base/test/scoped_task_scheduler.cc
@@ -47,6 +47,7 @@ class TestTaskScheduler : public TaskScheduler {
   ~TestTaskScheduler() override;
 
   // TaskScheduler:
+  void Start(const TaskScheduler::InitParams& init_params) override;
   void PostDelayedTaskWithTraits(const tracked_objects::Location& from_here,
                                  const TaskTraits& traits,
                                  OnceClosure task,
@@ -164,6 +165,13 @@ TestTaskScheduler::~TestTaskScheduler() {
     Shutdown();
 }
 
+void TestTaskScheduler::Start(const TaskScheduler::InitParams&) {
+  // ScopedTaskScheduler intentionally breaks the TaskScheduler contract of not

[robliao, 2017/04/24 22:32:19]

This comment should probably go at the top of TestTaskScheduler's declaration.

[gab, 2017/04/25 15:16:15]

Agreed, also this is another argument for getting rid of synchronous test task
scheduler.

[fdoray, 2017/04/25 18:43:35]

Done.

+  // running tasks before Start(). This avoid having to call Start() with dummy
+  // parameters.
+  NOTREACHED();
+}
+
 void TestTaskScheduler::PostDelayedTaskWithTraits(
     const tracked_objects::Location& from_here,
     const TaskTraits& traits,